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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // var str="i come from beijing";
        // var arr= str.split(" ");
        // arr.reverse();
        // str = arr.join(" ");
        // console.log(str)
        
        function rev(char){
            var str = char.split(" ").reverse().join(" ");
            return str;
        }
        console.log(rev("i come from beijing"));       
    </script>
</body>